Melanosis coli as a factor in the development of colorectal cancer

Abstract

Melanosis coli is characteristic of patients with a long history of constipation and the use of laxatives – anthraquinone derivatives, which are quite prescribed by doctors and patients independently. As a rule, melanosis develops after 4–9 months of taking drugs from this group and is most common in women in the older age group. Pathogenetically, melanosis is characterized by the deposition of pigment in the lamina propria of the mucous membrane, manifested by a pronounced dark coloration of the mucosa, depending on the degree of pigmentation of the colon, melanosis is divided into three degrees. The most common localization is in the right colon, but cases with the spread of pigmentation to the left colon and other parts have been described. Diagnosis does not cause difficulties, melanosis coli is detected during routine endoscopic examination, and is confirmed by pathomorphological examination. Melanosis is an actual problem in terms of the risk of developing colorectal cancer (CRC). There are already convincing data proving that the frequency of detection of adenomas increases not only due to the absence of pigment accumulation by them, but also the pathogenetic aspects of the influence of melanosis on the occurrence and development of adenomas have been described. Proteomic analysis allows to determine the expression of various proteins, which confirms the role of melanosis in the development of colorectal cancer. It is also interesting to note that sometimes there are some difficulties in the differential diagnosis of melanosis, for example, with ischemic lesions of the colon. Patients with melanosis coli require close attention, timely diagnosis and treatment.